1 /* 2 * ec.c - ACPI Embedded Controller Driver (v3) 3 * 4 * Copyright (C) 2001-2015 Intel Corporation 5 * Author: 2014, 2015 Lv Zheng <lv.zheng@intel.com> 6 * 2006, 2007 Alexey Starikovskiy <alexey.y.starikovskiy@intel.com> 7 * 2006 Denis Sadykov <denis.m.sadykov@intel.com> 8 * 2004 Luming Yu <luming.yu@intel.com> 9 * 2001, 2002 Andy Grover <andrew.grover@intel.com> 10 * 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com> 11 * Copyright (C) 2008 Alexey Starikovskiy <astarikovskiy@suse.de> 12 * 13 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 14 * 15 * This program is free software; you can redistribute it and/or modify 16 * it under the terms of the GNU General Public License as published by 17 * the Free Software Foundation; either version 2 of the License, or (at 18 * your option) any later version. 19 * 20 * This program is distributed in the hope that it will be useful, but 21 * WITHOUT ANY WARRANTY; without even the implied warranty of 22 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 23 * General Public License for more details. 24 * 25 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 26 */ 27 28 /* Uncomment next line to get verbose printout */ 29 /* #define DEBUG */ 30 #define pr_fmt(fmt) "ACPI : EC: " fmt 31 32 #include <linux/kernel.h> 33 #include <linux/module.h> 34 #include <linux/init.h> 35 #include <linux/types.h> 36 #include <linux/delay.h> 37 #include <linux/interrupt.h> 38 #include <linux/list.h> 39 #include <linux/spinlock.h> 40 #include <linux/slab.h> 41 #include <linux/acpi.h> 42 #include <linux/dmi.h> 43 #include <asm/io.h> 44 45 #include "internal.h" 46 47 #define ACPI_EC_CLASS "embedded_controller" 48 #define ACPI_EC_DEVICE_NAME "Embedded Controller" 49 #define ACPI_EC_FILE_INFO "info" 50 51 /* EC status register */ 52 #define ACPI_EC_FLAG_OBF 0x01 /* Output buffer full */ 53 #define ACPI_EC_FLAG_IBF 0x02 /* Input buffer full */ 54 #define ACPI_EC_FLAG_CMD 0x08 /* Input buffer contains a command */ 55 #define ACPI_EC_FLAG_BURST 0x10 /* burst mode */ 56 #define ACPI_EC_FLAG_SCI 0x20 /* EC-SCI occurred */ 57 58 /* 59 * The SCI_EVT clearing timing is not defined by the ACPI specification. 60 * This leads to lots of practical timing issues for the host EC driver. 61 * The following variations are defined (from the target EC firmware's 62 * perspective): 63 * STATUS: After indicating SCI_EVT edge triggered IRQ to the host, the 64 * target can clear SCI_EVT at any time so long as the host can see 65 * the indication by reading the status register (EC_SC). So the 66 * host should re-check SCI_EVT after the first time the SCI_EVT 67 * indication is seen, which is the same time the query request 68 * (QR_EC) is written to the command register (EC_CMD). SCI_EVT set 69 * at any later time could indicate another event. Normally such 70 * kind of EC firmware has implemented an event queue and will 71 * return 0x00 to indicate "no outstanding event". 72 * QUERY: After seeing the query request (QR_EC) written to the command 73 * register (EC_CMD) by the host and having prepared the responding 74 * event value in the data register (EC_DATA), the target can safely 75 * clear SCI_EVT because the target can confirm that the current 76 * event is being handled by the host. The host then should check 77 * SCI_EVT right after reading the event response from the data 78 * register (EC_DATA). 79 * EVENT: After seeing the event response read from the data register 80 * (EC_DATA) by the host, the target can clear SCI_EVT. As the 81 * target requires time to notice the change in the data register 82 * (EC_DATA), the host may be required to wait additional guarding 83 * time before checking the SCI_EVT again. Such guarding may not be 84 * necessary if the host is notified via another IRQ. 85 */ 86 #define ACPI_EC_EVT_TIMING_STATUS 0x00 87 #define ACPI_EC_EVT_TIMING_QUERY 0x01 88 #define ACPI_EC_EVT_TIMING_EVENT 0x02 89 90 /* EC commands */ 91 enum ec_command { 92 ACPI_EC_COMMAND_READ = 0x80, 93 ACPI_EC_COMMAND_WRITE = 0x81, 94 ACPI_EC_BURST_ENABLE = 0x82, 95 ACPI_EC_BURST_DISABLE = 0x83, 96 ACPI_EC_COMMAND_QUERY = 0x84, 97 }; 98 99 #define ACPI_EC_DELAY 500 /* Wait 500ms max. during EC ops */ 100 #define ACPI_EC_UDELAY_GLK 1000 /* Wait 1ms max. to get global lock */ 101 #define ACPI_EC_UDELAY_POLL 550 /* Wait 1ms for EC transaction polling */ 102 #define ACPI_EC_CLEAR_MAX 100 /* Maximum number of events to query 103 * when trying to clear the EC */ 104 105 enum { 106 EC_FLAGS_QUERY_PENDING, /* Query is pending */ 107 EC_FLAGS_QUERY_GUARDING, /* Guard for SCI_EVT check */ 108 EC_FLAGS_HANDLERS_INSTALLED, /* Handlers for GPE and 109 * OpReg are installed */ 110 EC_FLAGS_STARTED, /* Driver is started */ 111 EC_FLAGS_STOPPED, /* Driver is stopped */ 112 EC_FLAGS_COMMAND_STORM, /* GPE storms occurred to the 113 * current command processing */ 114 }; 115 116 #define ACPI_EC_COMMAND_POLL 0x01 /* Available for command byte */ 117 #define ACPI_EC_COMMAND_COMPLETE 0x02 /* Completed last byte */ 118 119 /* ec.c is compiled in acpi namespace so this shows up as acpi.ec_delay param */ 120 static unsigned int ec_delay __read_mostly = ACPI_EC_DELAY; 121 module_param(ec_delay, uint, 0644); 122 MODULE_PARM_DESC(ec_delay, "Timeout(ms) waited until an EC command completes"); 123 124 static bool ec_busy_polling __read_mostly; 125 module_param(ec_busy_polling, bool, 0644); 126 MODULE_PARM_DESC(ec_busy_polling, "Use busy polling to advance EC transaction"); 127 128 static unsigned int ec_polling_guard __read_mostly = ACPI_EC_UDELAY_POLL; 129 module_param(ec_polling_guard, uint, 0644); 130 MODULE_PARM_DESC(ec_polling_guard, "Guard time(us) between EC accesses in polling modes"); 131 132 static unsigned int ec_event_clearing __read_mostly = ACPI_EC_EVT_TIMING_QUERY; 133 134 /* 135 * If the number of false interrupts per one transaction exceeds 136 * this threshold, will think there is a GPE storm happened and 137 * will disable the GPE for normal transaction. 138 */ 139 static unsigned int ec_storm_threshold __read_mostly = 8; 140 module_param(ec_storm_threshold, uint, 0644); 141 MODULE_PARM_DESC(ec_storm_threshold, "Maxim false GPE numbers not considered as GPE storm"); 142 143 struct acpi_ec_query_handler { 144 struct list_head node; 145 acpi_ec_query_func func; 146 acpi_handle handle; 147 void *data; 148 u8 query_bit; 149 struct kref kref; 150 }; 151 152 struct transaction { 153 const u8 *wdata; 154 u8 *rdata; 155 unsigned short irq_count; 156 u8 command; 157 u8 wi; 158 u8 ri; 159 u8 wlen; 160 u8 rlen; 161 u8 flags; 162 }; 163 164 struct acpi_ec_query { 165 struct transaction transaction; 166 struct work_struct work; 167 struct acpi_ec_query_handler *handler; 168 }; 169 170 static int acpi_ec_query(struct acpi_ec *ec, u8 *data); 171 static void advance_transaction(struct acpi_ec *ec); 172 static void acpi_ec_event_handler(struct work_struct *work); 173 static void acpi_ec_event_processor(struct work_struct *work); 174 175 struct acpi_ec *boot_ec, *first_ec; 176 EXPORT_SYMBOL(first_ec); 177 178 static int EC_FLAGS_VALIDATE_ECDT; /* ASUStec ECDTs need to be validated */ 179 static int EC_FLAGS_SKIP_DSDT_SCAN; /* Not all BIOS survive early DSDT scan */ 180 static int EC_FLAGS_CLEAR_ON_RESUME; /* Needs acpi_ec_clear() on boot/resume */ 181 static int EC_FLAGS_QUERY_HANDSHAKE; /* Needs QR_EC issued when SCI_EVT set */ 182 183 /* -------------------------------------------------------------------------- 184 * Logging/Debugging 185 * -------------------------------------------------------------------------- */ 186 187 /* 188 * Splitters used by the developers to track the boundary of the EC 189 * handling processes. 190 */ 191 #ifdef DEBUG 192 #define EC_DBG_SEP " " 193 #define EC_DBG_DRV "+++++" 194 #define EC_DBG_STM "=====" 195 #define EC_DBG_REQ "*****" 196 #define EC_DBG_EVT "#####" 197 #else 198 #define EC_DBG_SEP "" 199 #define EC_DBG_DRV 200 #define EC_DBG_STM 201 #define EC_DBG_REQ 202 #define EC_DBG_EVT 203 #endif 204 205 #define ec_log_raw(fmt, ...) \ 206 pr_info(fmt "\n", ##__VA_ARGS__) 207 #define ec_dbg_raw(fmt, ...) \ 208 pr_debug(fmt "\n", ##__VA_ARGS__) 209 #define ec_log(filter, fmt, ...) \ 210 ec_log_raw(filter EC_DBG_SEP fmt EC_DBG_SEP filter, ##__VA_ARGS__) 211 #define ec_dbg(filter, fmt, ...) \ 212 ec_dbg_raw(filter EC_DBG_SEP fmt EC_DBG_SEP filter, ##__VA_ARGS__) 213 214 #define ec_log_drv(fmt, ...) \ 215 ec_log(EC_DBG_DRV, fmt, ##__VA_ARGS__) 216 #define ec_dbg_drv(fmt, ...) \ 217 ec_dbg(EC_DBG_DRV, fmt, ##__VA_ARGS__) 218 #define ec_dbg_stm(fmt, ...) \ 219 ec_dbg(EC_DBG_STM, fmt, ##__VA_ARGS__) 220 #define ec_dbg_req(fmt, ...) \ 221 ec_dbg(EC_DBG_REQ, fmt, ##__VA_ARGS__) 222 #define ec_dbg_evt(fmt, ...) \ 223 ec_dbg(EC_DBG_EVT, fmt, ##__VA_ARGS__) 224 #define ec_dbg_ref(ec, fmt, ...) \ 225 ec_dbg_raw("%lu: " fmt, ec->reference_count, ## __VA_ARGS__) 226 227 /* -------------------------------------------------------------------------- 228 * Device Flags 229 * -------------------------------------------------------------------------- */ 230 231 static bool acpi_ec_started(struct acpi_ec *ec) 232 { 233 return test_bit(EC_FLAGS_STARTED, &ec->flags) && 234 !test_bit(EC_FLAGS_STOPPED, &ec->flags); 235 } 236 237 static bool acpi_ec_flushed(struct acpi_ec *ec) 238 { 239 return ec->reference_count == 1; 240 } 241 242 /* -------------------------------------------------------------------------- 243 * EC Registers 244 * -------------------------------------------------------------------------- */ 245 246 static inline u8 acpi_ec_read_status(struct acpi_ec *ec) 247 { 248 u8 x = inb(ec->command_addr); 249 250 ec_dbg_raw("EC_SC(R) = 0x%2.2x " 251 "SCI_EVT=%d BURST=%d CMD=%d IBF=%d OBF=%d", 252 x, 253 !!(x & ACPI_EC_FLAG_SCI), 254 !!(x & ACPI_EC_FLAG_BURST), 255 !!(x & ACPI_EC_FLAG_CMD), 256 !!(x & ACPI_EC_FLAG_IBF), 257 !!(x & ACPI_EC_FLAG_OBF)); 258 return x; 259 } 260 261 static inline u8 acpi_ec_read_data(struct acpi_ec *ec) 262 { 263 u8 x = inb(ec->data_addr); 264 265 ec->timestamp = jiffies; 266 ec_dbg_raw("EC_DATA(R) = 0x%2.2x", x); 267 return x; 268 } 269 270 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command) 271 { 272 ec_dbg_raw("EC_SC(W) = 0x%2.2x", command); 273 outb(command, ec->command_addr); 274 ec->timestamp = jiffies; 275 } 276 277 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data) 278 { 279 ec_dbg_raw("EC_DATA(W) = 0x%2.2x", data); 280 outb(data, ec->data_addr); 281 ec->timestamp = jiffies; 282 } 283 284 #ifdef DEBUG 285 static const char *acpi_ec_cmd_string(u8 cmd) 286 { 287 switch (cmd) { 288 case 0x80: 289 return "RD_EC"; 290 case 0x81: 291 return "WR_EC"; 292 case 0x82: 293 return "BE_EC"; 294 case 0x83: 295 return "BD_EC"; 296 case 0x84: 297 return "QR_EC"; 298 } 299 return "UNKNOWN"; 300 } 301 #else 302 #define acpi_ec_cmd_string(cmd) "UNDEF" 303 #endif 304 305 /* -------------------------------------------------------------------------- 306 * GPE Registers 307 * -------------------------------------------------------------------------- */ 308 309 static inline bool acpi_ec_is_gpe_raised(struct acpi_ec *ec) 310 { 311 acpi_event_status gpe_status = 0; 312 313 (void)acpi_get_gpe_status(NULL, ec->gpe, &gpe_status); 314 return (gpe_status & ACPI_EVENT_FLAG_STATUS_SET) ? true : false; 315 } 316 317 static inline void acpi_ec_enable_gpe(struct acpi_ec *ec, bool open) 318 { 319 if (open) 320 acpi_enable_gpe(NULL, ec->gpe); 321 else { 322 BUG_ON(ec->reference_count < 1); 323 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_ENABLE); 324 } 325 if (acpi_ec_is_gpe_raised(ec)) { 326 /* 327 * On some platforms, EN=1 writes cannot trigger GPE. So 328 * software need to manually trigger a pseudo GPE event on 329 * EN=1 writes. 330 */ 331 ec_dbg_raw("Polling quirk"); 332 advance_transaction(ec); 333 } 334 } 335 336 static inline void acpi_ec_disable_gpe(struct acpi_ec *ec, bool close) 337 { 338 if (close) 339 acpi_disable_gpe(NULL, ec->gpe); 340 else { 341 BUG_ON(ec->reference_count < 1); 342 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_DISABLE); 343 } 344 } 345 346 static inline void acpi_ec_clear_gpe(struct acpi_ec *ec) 347 { 348 /* 349 * GPE STS is a W1C register, which means: 350 * 1. Software can clear it without worrying about clearing other 351 * GPEs' STS bits when the hardware sets them in parallel. 352 * 2. As long as software can ensure only clearing it when it is 353 * set, hardware won't set it in parallel. 354 * So software can clear GPE in any contexts. 355 * Warning: do not move the check into advance_transaction() as the 356 * EC commands will be sent without GPE raised. 357 */ 358 if (!acpi_ec_is_gpe_raised(ec)) 359 return; 360 acpi_clear_gpe(NULL, ec->gpe); 361 } 362 363 /* -------------------------------------------------------------------------- 364 * Transaction Management 365 * -------------------------------------------------------------------------- */ 366 367 static void acpi_ec_submit_request(struct acpi_ec *ec) 368 { 369 ec->reference_count++; 370 if (ec->reference_count == 1) 371 acpi_ec_enable_gpe(ec, true); 372 } 373 374 static void acpi_ec_complete_request(struct acpi_ec *ec) 375 { 376 bool flushed = false; 377 378 ec->reference_count--; 379 if (ec->reference_count == 0) 380 acpi_ec_disable_gpe(ec, true); 381 flushed = acpi_ec_flushed(ec); 382 if (flushed) 383 wake_up(&ec->wait); 384 } 385 386 static void acpi_ec_set_storm(struct acpi_ec *ec, u8 flag) 387 { 388 if (!test_bit(flag, &ec->flags)) { 389 acpi_ec_disable_gpe(ec, false); 390 ec_dbg_drv("Polling enabled"); 391 set_bit(flag, &ec->flags); 392 } 393 } 394 395 static void acpi_ec_clear_storm(struct acpi_ec *ec, u8 flag) 396 { 397 if (test_bit(flag, &ec->flags)) { 398 clear_bit(flag, &ec->flags); 399 acpi_ec_enable_gpe(ec, false); 400 ec_dbg_drv("Polling disabled"); 401 } 402 } 403 404 /* 405 * acpi_ec_submit_flushable_request() - Increase the reference count unless 406 * the flush operation is not in 407 * progress 408 * @ec: the EC device 409 * 410 * This function must be used before taking a new action that should hold 411 * the reference count. If this function returns false, then the action 412 * must be discarded or it will prevent the flush operation from being 413 * completed. 414 */ 415 static bool acpi_ec_submit_flushable_request(struct acpi_ec *ec) 416 { 417 if (!acpi_ec_started(ec)) 418 return false; 419 acpi_ec_submit_request(ec); 420 return true; 421 } 422 423 static void acpi_ec_submit_query(struct acpi_ec *ec) 424 { 425 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) { 426 ec_dbg_evt("Command(%s) submitted/blocked", 427 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); 428 ec->nr_pending_queries++; 429 schedule_work(&ec->work); 430 } 431 } 432 433 static void acpi_ec_complete_query(struct acpi_ec *ec) 434 { 435 if (test_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) { 436 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags); 437 ec_dbg_evt("Command(%s) unblocked", 438 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); 439 } 440 } 441 442 static bool acpi_ec_guard_event(struct acpi_ec *ec) 443 { 444 if (ec_event_clearing == ACPI_EC_EVT_TIMING_STATUS || 445 ec_event_clearing == ACPI_EC_EVT_TIMING_QUERY || 446 !test_bit(EC_FLAGS_QUERY_PENDING, &ec->flags) || 447 (ec->curr && ec->curr->command == ACPI_EC_COMMAND_QUERY)) 448 return false; 449 450 /* 451 * Postpone the query submission to allow the firmware to proceed, 452 * we shouldn't check SCI_EVT before the firmware reflagging it. 453 */ 454 return true; 455 } 456 457 static int ec_transaction_polled(struct acpi_ec *ec) 458 { 459 unsigned long flags; 460 int ret = 0; 461 462 spin_lock_irqsave(&ec->lock, flags); 463 if (ec->curr && (ec->curr->flags & ACPI_EC_COMMAND_POLL)) 464 ret = 1; 465 spin_unlock_irqrestore(&ec->lock, flags); 466 return ret; 467 } 468 469 static int ec_transaction_completed(struct acpi_ec *ec) 470 { 471 unsigned long flags; 472 int ret = 0; 473 474 spin_lock_irqsave(&ec->lock, flags); 475 if (ec->curr && (ec->curr->flags & ACPI_EC_COMMAND_COMPLETE)) 476 ret = 1; 477 spin_unlock_irqrestore(&ec->lock, flags); 478 return ret; 479 } 480 481 static inline void ec_transaction_transition(struct acpi_ec *ec, unsigned long flag) 482 { 483 ec->curr->flags |= flag; 484 if (ec->curr->command == ACPI_EC_COMMAND_QUERY) { 485 if (ec_event_clearing == ACPI_EC_EVT_TIMING_STATUS && 486 flag == ACPI_EC_COMMAND_POLL) 487 acpi_ec_complete_query(ec); 488 if (ec_event_clearing == ACPI_EC_EVT_TIMING_QUERY && 489 flag == ACPI_EC_COMMAND_COMPLETE) 490 acpi_ec_complete_query(ec); 491 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT && 492 flag == ACPI_EC_COMMAND_COMPLETE) 493 set_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags); 494 } 495 } 496 497 static void advance_transaction(struct acpi_ec *ec) 498 { 499 struct transaction *t; 500 u8 status; 501 bool wakeup = false; 502 503 ec_dbg_stm("%s (%d)", in_interrupt() ? "IRQ" : "TASK", 504 smp_processor_id()); 505 /* 506 * By always clearing STS before handling all indications, we can 507 * ensure a hardware STS 0->1 change after this clearing can always 508 * trigger a GPE interrupt. 509 */ 510 acpi_ec_clear_gpe(ec); 511 status = acpi_ec_read_status(ec); 512 t = ec->curr; 513 /* 514 * Another IRQ or a guarded polling mode advancement is detected, 515 * the next QR_EC submission is then allowed. 516 */ 517 if (!t || !(t->flags & ACPI_EC_COMMAND_POLL)) { 518 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT && 519 (!ec->nr_pending_queries || 520 test_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags))) { 521 clear_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags); 522 acpi_ec_complete_query(ec); 523 } 524 } 525 if (!t) 526 goto err; 527 if (t->flags & ACPI_EC_COMMAND_POLL) { 528 if (t->wlen > t->wi) { 529 if ((status & ACPI_EC_FLAG_IBF) == 0) 530 acpi_ec_write_data(ec, t->wdata[t->wi++]); 531 else 532 goto err; 533 } else if (t->rlen > t->ri) { 534 if ((status & ACPI_EC_FLAG_OBF) == 1) { 535 t->rdata[t->ri++] = acpi_ec_read_data(ec); 536 if (t->rlen == t->ri) { 537 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE); 538 if (t->command == ACPI_EC_COMMAND_QUERY) 539 ec_dbg_evt("Command(%s) completed by hardware", 540 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); 541 wakeup = true; 542 } 543 } else 544 goto err; 545 } else if (t->wlen == t->wi && 546 (status & ACPI_EC_FLAG_IBF) == 0) { 547 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE); 548 wakeup = true; 549 } 550 goto out; 551 } else { 552 if (EC_FLAGS_QUERY_HANDSHAKE && 553 !(status & ACPI_EC_FLAG_SCI) && 554 (t->command == ACPI_EC_COMMAND_QUERY)) { 555 ec_transaction_transition(ec, ACPI_EC_COMMAND_POLL); 556 t->rdata[t->ri++] = 0x00; 557 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE); 558 ec_dbg_evt("Command(%s) completed by software", 559 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); 560 wakeup = true; 561 } else if ((status & ACPI_EC_FLAG_IBF) == 0) { 562 acpi_ec_write_cmd(ec, t->command); 563 ec_transaction_transition(ec, ACPI_EC_COMMAND_POLL); 564 } else 565 goto err; 566 goto out; 567 } 568 err: 569 /* 570 * If SCI bit is set, then don't think it's a false IRQ 571 * otherwise will take a not handled IRQ as a false one. 572 */ 573 if (!(status & ACPI_EC_FLAG_SCI)) { 574 if (in_interrupt() && t) { 575 if (t->irq_count < ec_storm_threshold) 576 ++t->irq_count; 577 /* Allow triggering on 0 threshold */ 578 if (t->irq_count == ec_storm_threshold) 579 acpi_ec_set_storm(ec, EC_FLAGS_COMMAND_STORM); 580 } 581 } 582 out: 583 if (status & ACPI_EC_FLAG_SCI) 584 acpi_ec_submit_query(ec); 585 if (wakeup && in_interrupt()) 586 wake_up(&ec->wait); 587 } 588 589 static void start_transaction(struct acpi_ec *ec) 590 { 591 ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0; 592 ec->curr->flags = 0; 593 } 594 595 static int ec_guard(struct acpi_ec *ec) 596 { 597 unsigned long guard = usecs_to_jiffies(ec_polling_guard); 598 unsigned long timeout = ec->timestamp + guard; 599 600 do { 601 if (ec_busy_polling) { 602 /* Perform busy polling */ 603 if (ec_transaction_completed(ec)) 604 return 0; 605 udelay(jiffies_to_usecs(guard)); 606 } else { 607 /* 608 * Perform wait polling 609 * 610 * For SCI_EVT clearing timing of "event", 611 * performing guarding before re-checking the 612 * SCI_EVT. Otherwise, such guarding is not needed 613 * due to the old practices. 614 */ 615 if (!ec_transaction_polled(ec) && 616 !acpi_ec_guard_event(ec)) 617 break; 618 if (wait_event_timeout(ec->wait, 619 ec_transaction_completed(ec), 620 guard)) 621 return 0; 622 } 623 /* Guard the register accesses for the polling modes */ 624 } while (time_before(jiffies, timeout)); 625 return -ETIME; 626 } 627 628 static int ec_poll(struct acpi_ec *ec) 629 { 630 unsigned long flags; 631 int repeat = 5; /* number of command restarts */ 632 633 while (repeat--) { 634 unsigned long delay = jiffies + 635 msecs_to_jiffies(ec_delay); 636 do { 637 if (!ec_guard(ec)) 638 return 0; 639 spin_lock_irqsave(&ec->lock, flags); 640 advance_transaction(ec); 641 spin_unlock_irqrestore(&ec->lock, flags); 642 } while (time_before(jiffies, delay)); 643 pr_debug("controller reset, restart transaction\n"); 644 spin_lock_irqsave(&ec->lock, flags); 645 start_transaction(ec); 646 spin_unlock_irqrestore(&ec->lock, flags); 647 } 648 return -ETIME; 649 } 650 651 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec, 652 struct transaction *t) 653 { 654 unsigned long tmp; 655 int ret = 0; 656 657 /* start transaction */ 658 spin_lock_irqsave(&ec->lock, tmp); 659 /* Enable GPE for command processing (IBF=0/OBF=1) */ 660 if (!acpi_ec_submit_flushable_request(ec)) { 661 ret = -EINVAL; 662 goto unlock; 663 } 664 ec_dbg_ref(ec, "Increase command"); 665 /* following two actions should be kept atomic */ 666 ec->curr = t; 667 ec_dbg_req("Command(%s) started", acpi_ec_cmd_string(t->command)); 668 start_transaction(ec); 669 spin_unlock_irqrestore(&ec->lock, tmp); 670 671 ret = ec_poll(ec); 672 673 spin_lock_irqsave(&ec->lock, tmp); 674 if (t->irq_count == ec_storm_threshold) 675 acpi_ec_clear_storm(ec, EC_FLAGS_COMMAND_STORM); 676 ec_dbg_req("Command(%s) stopped", acpi_ec_cmd_string(t->command)); 677 ec->curr = NULL; 678 /* Disable GPE for command processing (IBF=0/OBF=1) */ 679 acpi_ec_complete_request(ec); 680 ec_dbg_ref(ec, "Decrease command"); 681 unlock: 682 spin_unlock_irqrestore(&ec->lock, tmp); 683 return ret; 684 } 685 686 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t) 687 { 688 int status; 689 u32 glk; 690 691 if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata)) 692 return -EINVAL; 693 if (t->rdata) 694 memset(t->rdata, 0, t->rlen); 695 696 mutex_lock(&ec->mutex); 697 if (ec->global_lock) { 698 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk); 699 if (ACPI_FAILURE(status)) { 700 status = -ENODEV; 701 goto unlock; 702 } 703 } 704 705 status = acpi_ec_transaction_unlocked(ec, t); 706 707 if (ec->global_lock) 708 acpi_release_global_lock(glk); 709 unlock: 710 mutex_unlock(&ec->mutex); 711 return status; 712 } 713 714 static int acpi_ec_burst_enable(struct acpi_ec *ec) 715 { 716 u8 d; 717 struct transaction t = {.command = ACPI_EC_BURST_ENABLE, 718 .wdata = NULL, .rdata = &d, 719 .wlen = 0, .rlen = 1}; 720 721 return acpi_ec_transaction(ec, &t); 722 } 723 724 static int acpi_ec_burst_disable(struct acpi_ec *ec) 725 { 726 struct transaction t = {.command = ACPI_EC_BURST_DISABLE, 727 .wdata = NULL, .rdata = NULL, 728 .wlen = 0, .rlen = 0}; 729 730 return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ? 731 acpi_ec_transaction(ec, &t) : 0; 732 } 733 734 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 *data) 735 { 736 int result; 737 u8 d; 738 struct transaction t = {.command = ACPI_EC_COMMAND_READ, 739 .wdata = &address, .rdata = &d, 740 .wlen = 1, .rlen = 1}; 741 742 result = acpi_ec_transaction(ec, &t); 743 *data = d; 744 return result; 745 } 746 747 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data) 748 { 749 u8 wdata[2] = { address, data }; 750 struct transaction t = {.command = ACPI_EC_COMMAND_WRITE, 751 .wdata = wdata, .rdata = NULL, 752 .wlen = 2, .rlen = 0}; 753 754 return acpi_ec_transaction(ec, &t); 755 } 756 757 int ec_read(u8 addr, u8 *val) 758 { 759 int err; 760 u8 temp_data; 761 762 if (!first_ec) 763 return -ENODEV; 764 765 err = acpi_ec_read(first_ec, addr, &temp_data); 766 767 if (!err) { 768 *val = temp_data; 769 return 0; 770 } 771 return err; 772 } 773 EXPORT_SYMBOL(ec_read); 774 775 int ec_write(u8 addr, u8 val) 776 { 777 int err; 778 779 if (!first_ec) 780 return -ENODEV; 781 782 err = acpi_ec_write(first_ec, addr, val); 783 784 return err; 785 } 786 EXPORT_SYMBOL(ec_write); 787 788 int ec_transaction(u8 command, 789 const u8 *wdata, unsigned wdata_len, 790 u8 *rdata, unsigned rdata_len) 791 { 792 struct transaction t = {.command = command, 793 .wdata = wdata, .rdata = rdata, 794 .wlen = wdata_len, .rlen = rdata_len}; 795 796 if (!first_ec) 797 return -ENODEV; 798 799 return acpi_ec_transaction(first_ec, &t); 800 } 801 EXPORT_SYMBOL(ec_transaction); 802 803 /* Get the handle to the EC device */ 804 acpi_handle ec_get_handle(void) 805 { 806 if (!first_ec) 807 return NULL; 808 return first_ec->handle; 809 } 810 EXPORT_SYMBOL(ec_get_handle); 811 812 /* 813 * Process _Q events that might have accumulated in the EC. 814 * Run with locked ec mutex. 815 */ 816 static void acpi_ec_clear(struct acpi_ec *ec) 817 { 818 int i, status; 819 u8 value = 0; 820 821 for (i = 0; i < ACPI_EC_CLEAR_MAX; i++) { 822 status = acpi_ec_query(ec, &value); 823 if (status || !value) 824 break; 825 } 826 827 if (unlikely(i == ACPI_EC_CLEAR_MAX)) 828 pr_warn("Warning: Maximum of %d stale EC events cleared\n", i); 829 else 830 pr_info("%d stale EC events cleared\n", i); 831 } 832 833 static void acpi_ec_start(struct acpi_ec *ec, bool resuming) 834 { 835 unsigned long flags; 836 837 spin_lock_irqsave(&ec->lock, flags); 838 if (!test_and_set_bit(EC_FLAGS_STARTED, &ec->flags)) { 839 ec_dbg_drv("Starting EC"); 840 /* Enable GPE for event processing (SCI_EVT=1) */ 841 if (!resuming) { 842 acpi_ec_submit_request(ec); 843 ec_dbg_ref(ec, "Increase driver"); 844 } 845 ec_log_drv("EC started"); 846 } 847 spin_unlock_irqrestore(&ec->lock, flags); 848 } 849 850 static bool acpi_ec_stopped(struct acpi_ec *ec) 851 { 852 unsigned long flags; 853 bool flushed; 854 855 spin_lock_irqsave(&ec->lock, flags); 856 flushed = acpi_ec_flushed(ec); 857 spin_unlock_irqrestore(&ec->lock, flags); 858 return flushed; 859 } 860 861 static void acpi_ec_stop(struct acpi_ec *ec, bool suspending) 862 { 863 unsigned long flags; 864 865 spin_lock_irqsave(&ec->lock, flags); 866 if (acpi_ec_started(ec)) { 867 ec_dbg_drv("Stopping EC"); 868 set_bit(EC_FLAGS_STOPPED, &ec->flags); 869 spin_unlock_irqrestore(&ec->lock, flags); 870 wait_event(ec->wait, acpi_ec_stopped(ec)); 871 spin_lock_irqsave(&ec->lock, flags); 872 /* Disable GPE for event processing (SCI_EVT=1) */ 873 if (!suspending) { 874 acpi_ec_complete_request(ec); 875 ec_dbg_ref(ec, "Decrease driver"); 876 } 877 clear_bit(EC_FLAGS_STARTED, &ec->flags); 878 clear_bit(EC_FLAGS_STOPPED, &ec->flags); 879 ec_log_drv("EC stopped"); 880 } 881 spin_unlock_irqrestore(&ec->lock, flags); 882 } 883 884 void acpi_ec_block_transactions(void) 885 { 886 struct acpi_ec *ec = first_ec; 887 888 if (!ec) 889 return; 890 891 mutex_lock(&ec->mutex); 892 /* Prevent transactions from being carried out */ 893 acpi_ec_stop(ec, true); 894 mutex_unlock(&ec->mutex); 895 } 896 897 void acpi_ec_unblock_transactions(void) 898 { 899 struct acpi_ec *ec = first_ec; 900 901 if (!ec) 902 return; 903 904 /* Allow transactions to be carried out again */ 905 acpi_ec_start(ec, true); 906 907 if (EC_FLAGS_CLEAR_ON_RESUME) 908 acpi_ec_clear(ec); 909 } 910 911 void acpi_ec_unblock_transactions_early(void) 912 { 913 /* 914 * Allow transactions to happen again (this function is called from 915 * atomic context during wakeup, so we don't need to acquire the mutex). 916 */ 917 if (first_ec) 918 acpi_ec_start(first_ec, true); 919 } 920 921 /* -------------------------------------------------------------------------- 922 Event Management 923 -------------------------------------------------------------------------- */ 924 static struct acpi_ec_query_handler * 925 acpi_ec_get_query_handler(struct acpi_ec_query_handler *handler) 926 { 927 if (handler) 928 kref_get(&handler->kref); 929 return handler; 930 } 931 932 static void acpi_ec_query_handler_release(struct kref *kref) 933 { 934 struct acpi_ec_query_handler *handler = 935 container_of(kref, struct acpi_ec_query_handler, kref); 936 937 kfree(handler); 938 } 939 940 static void acpi_ec_put_query_handler(struct acpi_ec_query_handler *handler) 941 { 942 kref_put(&handler->kref, acpi_ec_query_handler_release); 943 } 944 945 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit, 946 acpi_handle handle, acpi_ec_query_func func, 947 void *data) 948 { 949 struct acpi_ec_query_handler *handler = 950 kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL); 951 952 if (!handler) 953 return -ENOMEM; 954 955 handler->query_bit = query_bit; 956 handler->handle = handle; 957 handler->func = func; 958 handler->data = data; 959 mutex_lock(&ec->mutex); 960 kref_init(&handler->kref); 961 list_add(&handler->node, &ec->list); 962 mutex_unlock(&ec->mutex); 963 return 0; 964 } 965 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler); 966 967 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit) 968 { 969 struct acpi_ec_query_handler *handler, *tmp; 970 LIST_HEAD(free_list); 971 972 mutex_lock(&ec->mutex); 973 list_for_each_entry_safe(handler, tmp, &ec->list, node) { 974 if (query_bit == handler->query_bit) { 975 list_del_init(&handler->node); 976 list_add(&handler->node, &free_list); 977 } 978 } 979 mutex_unlock(&ec->mutex); 980 list_for_each_entry_safe(handler, tmp, &free_list, node) 981 acpi_ec_put_query_handler(handler); 982 } 983 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler); 984 985 static struct acpi_ec_query *acpi_ec_create_query(u8 *pval) 986 { 987 struct acpi_ec_query *q; 988 struct transaction *t; 989 990 q = kzalloc(sizeof (struct acpi_ec_query), GFP_KERNEL); 991 if (!q) 992 return NULL; 993 INIT_WORK(&q->work, acpi_ec_event_processor); 994 t = &q->transaction; 995 t->command = ACPI_EC_COMMAND_QUERY; 996 t->rdata = pval; 997 t->rlen = 1; 998 return q; 999 } 1000 1001 static void acpi_ec_delete_query(struct acpi_ec_query *q) 1002 { 1003 if (q) { 1004 if (q->handler) 1005 acpi_ec_put_query_handler(q->handler); 1006 kfree(q); 1007 } 1008 } 1009 1010 static void acpi_ec_event_processor(struct work_struct *work) 1011 { 1012 struct acpi_ec_query *q = container_of(work, struct acpi_ec_query, work); 1013 struct acpi_ec_query_handler *handler = q->handler; 1014 1015 ec_dbg_evt("Query(0x%02x) started", handler->query_bit); 1016 if (handler->func) 1017 handler->func(handler->data); 1018 else if (handler->handle) 1019 acpi_evaluate_object(handler->handle, NULL, NULL, NULL); 1020 ec_dbg_evt("Query(0x%02x) stopped", handler->query_bit); 1021 acpi_ec_delete_query(q); 1022 } 1023 1024 static int acpi_ec_query(struct acpi_ec *ec, u8 *data) 1025 { 1026 u8 value = 0; 1027 int result; 1028 struct acpi_ec_query_handler *handler; 1029 struct acpi_ec_query *q; 1030 1031 q = acpi_ec_create_query(&value); 1032 if (!q) 1033 return -ENOMEM; 1034 1035 /* 1036 * Query the EC to find out which _Qxx method we need to evaluate. 1037 * Note that successful completion of the query causes the ACPI_EC_SCI 1038 * bit to be cleared (and thus clearing the interrupt source). 1039 */ 1040 result = acpi_ec_transaction(ec, &q->transaction); 1041 if (!value) 1042 result = -ENODATA; 1043 if (result) 1044 goto err_exit; 1045 1046 mutex_lock(&ec->mutex); 1047 result = -ENODATA; 1048 list_for_each_entry(handler, &ec->list, node) { 1049 if (value == handler->query_bit) { 1050 result = 0; 1051 q->handler = acpi_ec_get_query_handler(handler); 1052 ec_dbg_evt("Query(0x%02x) scheduled", 1053 q->handler->query_bit); 1054 /* 1055 * It is reported that _Qxx are evaluated in a 1056 * parallel way on Windows: 1057 * https://bugzilla.kernel.org/show_bug.cgi?id=94411 1058 */ 1059 if (!schedule_work(&q->work)) 1060 result = -EBUSY; 1061 break; 1062 } 1063 } 1064 mutex_unlock(&ec->mutex); 1065 1066 err_exit: 1067 if (result && q) 1068 acpi_ec_delete_query(q); 1069 if (data) 1070 *data = value; 1071 return result; 1072 } 1073 1074 static void acpi_ec_check_event(struct acpi_ec *ec) 1075 { 1076 unsigned long flags; 1077 1078 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT) { 1079 if (ec_guard(ec)) { 1080 spin_lock_irqsave(&ec->lock, flags); 1081 /* 1082 * Take care of the SCI_EVT unless no one else is 1083 * taking care of it. 1084 */ 1085 if (!ec->curr) 1086 advance_transaction(ec); 1087 spin_unlock_irqrestore(&ec->lock, flags); 1088 } 1089 } 1090 } 1091 1092 static void acpi_ec_event_handler(struct work_struct *work) 1093 { 1094 unsigned long flags; 1095 struct acpi_ec *ec = container_of(work, struct acpi_ec, work); 1096 1097 ec_dbg_evt("Event started"); 1098 1099 spin_lock_irqsave(&ec->lock, flags); 1100 while (ec->nr_pending_queries) { 1101 spin_unlock_irqrestore(&ec->lock, flags); 1102 (void)acpi_ec_query(ec, NULL); 1103 spin_lock_irqsave(&ec->lock, flags); 1104 ec->nr_pending_queries--; 1105 /* 1106 * Before exit, make sure that this work item can be 1107 * scheduled again. There might be QR_EC failures, leaving 1108 * EC_FLAGS_QUERY_PENDING uncleared and preventing this work 1109 * item from being scheduled again. 1110 */ 1111 if (!ec->nr_pending_queries) { 1112 if (ec_event_clearing == ACPI_EC_EVT_TIMING_STATUS || 1113 ec_event_clearing == ACPI_EC_EVT_TIMING_QUERY) 1114 acpi_ec_complete_query(ec); 1115 } 1116 } 1117 spin_unlock_irqrestore(&ec->lock, flags); 1118 1119 ec_dbg_evt("Event stopped"); 1120 1121 acpi_ec_check_event(ec); 1122 } 1123 1124 static u32 acpi_ec_gpe_handler(acpi_handle gpe_device, 1125 u32 gpe_number, void *data) 1126 { 1127 unsigned long flags; 1128 struct acpi_ec *ec = data; 1129 1130 spin_lock_irqsave(&ec->lock, flags); 1131 advance_transaction(ec); 1132 spin_unlock_irqrestore(&ec->lock, flags); 1133 return ACPI_INTERRUPT_HANDLED; 1134 } 1135 1136 /* -------------------------------------------------------------------------- 1137 * Address Space Management 1138 * -------------------------------------------------------------------------- */ 1139 1140 static acpi_status 1141 acpi_ec_space_handler(u32 function, acpi_physical_address address, 1142 u32 bits, u64 *value64, 1143 void *handler_context, void *region_context) 1144 { 1145 struct acpi_ec *ec = handler_context; 1146 int result = 0, i, bytes = bits / 8; 1147 u8 *value = (u8 *)value64; 1148 1149 if ((address > 0xFF) || !value || !handler_context) 1150 return AE_BAD_PARAMETER; 1151 1152 if (function != ACPI_READ && function != ACPI_WRITE) 1153 return AE_BAD_PARAMETER; 1154 1155 if (ec_busy_polling || bits > 8) 1156 acpi_ec_burst_enable(ec); 1157 1158 for (i = 0; i < bytes; ++i, ++address, ++value) 1159 result = (function == ACPI_READ) ? 1160 acpi_ec_read(ec, address, value) : 1161 acpi_ec_write(ec, address, *value); 1162 1163 if (ec_busy_polling || bits > 8) 1164 acpi_ec_burst_disable(ec); 1165 1166 switch (result) { 1167 case -EINVAL: 1168 return AE_BAD_PARAMETER; 1169 case -ENODEV: 1170 return AE_NOT_FOUND; 1171 case -ETIME: 1172 return AE_TIME; 1173 default: 1174 return AE_OK; 1175 } 1176 } 1177 1178 /* -------------------------------------------------------------------------- 1179 * Driver Interface 1180 * -------------------------------------------------------------------------- */ 1181 1182 static acpi_status 1183 ec_parse_io_ports(struct acpi_resource *resource, void *context); 1184 1185 static struct acpi_ec *make_acpi_ec(void) 1186 { 1187 struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL); 1188 1189 if (!ec) 1190 return NULL; 1191 ec->flags = 1 << EC_FLAGS_QUERY_PENDING; 1192 mutex_init(&ec->mutex); 1193 init_waitqueue_head(&ec->wait); 1194 INIT_LIST_HEAD(&ec->list); 1195 spin_lock_init(&ec->lock); 1196 INIT_WORK(&ec->work, acpi_ec_event_handler); 1197 ec->timestamp = jiffies; 1198 return ec; 1199 } 1200 1201 static acpi_status 1202 acpi_ec_register_query_methods(acpi_handle handle, u32 level, 1203 void *context, void **return_value) 1204 { 1205 char node_name[5]; 1206 struct acpi_buffer buffer = { sizeof(node_name), node_name }; 1207 struct acpi_ec *ec = context; 1208 int value = 0; 1209 acpi_status status; 1210 1211 status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer); 1212 1213 if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1) 1214 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL); 1215 return AE_OK; 1216 } 1217 1218 static acpi_status 1219 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval) 1220 { 1221 acpi_status status; 1222 unsigned long long tmp = 0; 1223 struct acpi_ec *ec = context; 1224 1225 /* clear addr values, ec_parse_io_ports depend on it */ 1226 ec->command_addr = ec->data_addr = 0; 1227 1228 status = acpi_walk_resources(handle, METHOD_NAME__CRS, 1229 ec_parse_io_ports, ec); 1230 if (ACPI_FAILURE(status)) 1231 return status; 1232 1233 /* Get GPE bit assignment (EC events). */ 1234 /* TODO: Add support for _GPE returning a package */ 1235 status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp); 1236 if (ACPI_FAILURE(status)) 1237 return status; 1238 ec->gpe = tmp; 1239 /* Use the global lock for all EC transactions? */ 1240 tmp = 0; 1241 acpi_evaluate_integer(handle, "_GLK", NULL, &tmp); 1242 ec->global_lock = tmp; 1243 ec->handle = handle; 1244 return AE_CTRL_TERMINATE; 1245 } 1246 1247 static int ec_install_handlers(struct acpi_ec *ec) 1248 { 1249 acpi_status status; 1250 1251 if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags)) 1252 return 0; 1253 status = acpi_install_gpe_raw_handler(NULL, ec->gpe, 1254 ACPI_GPE_EDGE_TRIGGERED, 1255 &acpi_ec_gpe_handler, ec); 1256 if (ACPI_FAILURE(status)) 1257 return -ENODEV; 1258 1259 acpi_ec_start(ec, false); 1260 status = acpi_install_address_space_handler(ec->handle, 1261 ACPI_ADR_SPACE_EC, 1262 &acpi_ec_space_handler, 1263 NULL, ec); 1264 if (ACPI_FAILURE(status)) { 1265 if (status == AE_NOT_FOUND) { 1266 /* 1267 * Maybe OS fails in evaluating the _REG object. 1268 * The AE_NOT_FOUND error will be ignored and OS 1269 * continue to initialize EC. 1270 */ 1271 pr_err("Fail in evaluating the _REG object" 1272 " of EC device. Broken bios is suspected.\n"); 1273 } else { 1274 acpi_ec_stop(ec, false); 1275 acpi_remove_gpe_handler(NULL, ec->gpe, 1276 &acpi_ec_gpe_handler); 1277 return -ENODEV; 1278 } 1279 } 1280 1281 set_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags); 1282 return 0; 1283 } 1284 1285 static void ec_remove_handlers(struct acpi_ec *ec) 1286 { 1287 if (!test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags)) 1288 return; 1289 acpi_ec_stop(ec, false); 1290 if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle, 1291 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler))) 1292 pr_err("failed to remove space handler\n"); 1293 if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe, 1294 &acpi_ec_gpe_handler))) 1295 pr_err("failed to remove gpe handler\n"); 1296 clear_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags); 1297 } 1298 1299 static int acpi_ec_add(struct acpi_device *device) 1300 { 1301 struct acpi_ec *ec = NULL; 1302 int ret; 1303 1304 strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME); 1305 strcpy(acpi_device_class(device), ACPI_EC_CLASS); 1306 1307 /* Check for boot EC */ 1308 if (boot_ec && 1309 (boot_ec->handle == device->handle || 1310 boot_ec->handle == ACPI_ROOT_OBJECT)) { 1311 ec = boot_ec; 1312 boot_ec = NULL; 1313 } else { 1314 ec = make_acpi_ec(); 1315 if (!ec) 1316 return -ENOMEM; 1317 } 1318 if (ec_parse_device(device->handle, 0, ec, NULL) != 1319 AE_CTRL_TERMINATE) { 1320 kfree(ec); 1321 return -EINVAL; 1322 } 1323 1324 /* Find and register all query methods */ 1325 acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1, 1326 acpi_ec_register_query_methods, NULL, ec, NULL); 1327 1328 if (!first_ec) 1329 first_ec = ec; 1330 device->driver_data = ec; 1331 1332 ret = !!request_region(ec->data_addr, 1, "EC data"); 1333 WARN(!ret, "Could not request EC data io port 0x%lx", ec->data_addr); 1334 ret = !!request_region(ec->command_addr, 1, "EC cmd"); 1335 WARN(!ret, "Could not request EC cmd io port 0x%lx", ec->command_addr); 1336 1337 pr_info("GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n", 1338 ec->gpe, ec->command_addr, ec->data_addr); 1339 1340 ret = ec_install_handlers(ec); 1341 1342 /* Reprobe devices depending on the EC */ 1343 acpi_walk_dep_device_list(ec->handle); 1344 1345 /* EC is fully operational, allow queries */ 1346 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags); 1347 1348 /* Clear stale _Q events if hardware might require that */ 1349 if (EC_FLAGS_CLEAR_ON_RESUME) 1350 acpi_ec_clear(ec); 1351 return ret; 1352 } 1353 1354 static int acpi_ec_remove(struct acpi_device *device) 1355 { 1356 struct acpi_ec *ec; 1357 struct acpi_ec_query_handler *handler, *tmp; 1358 1359 if (!device) 1360 return -EINVAL; 1361 1362 ec = acpi_driver_data(device); 1363 ec_remove_handlers(ec); 1364 mutex_lock(&ec->mutex); 1365 list_for_each_entry_safe(handler, tmp, &ec->list, node) { 1366 list_del(&handler->node); 1367 kfree(handler); 1368 } 1369 mutex_unlock(&ec->mutex); 1370 release_region(ec->data_addr, 1); 1371 release_region(ec->command_addr, 1); 1372 device->driver_data = NULL; 1373 if (ec == first_ec) 1374 first_ec = NULL; 1375 kfree(ec); 1376 return 0; 1377 } 1378 1379 static acpi_status 1380 ec_parse_io_ports(struct acpi_resource *resource, void *context) 1381 { 1382 struct acpi_ec *ec = context; 1383 1384 if (resource->type != ACPI_RESOURCE_TYPE_IO) 1385 return AE_OK; 1386 1387 /* 1388 * The first address region returned is the data port, and 1389 * the second address region returned is the status/command 1390 * port. 1391 */ 1392 if (ec->data_addr == 0) 1393 ec->data_addr = resource->data.io.minimum; 1394 else if (ec->command_addr == 0) 1395 ec->command_addr = resource->data.io.minimum; 1396 else 1397 return AE_CTRL_TERMINATE; 1398 1399 return AE_OK; 1400 } 1401 1402 int __init acpi_boot_ec_enable(void) 1403 { 1404 if (!boot_ec || test_bit(EC_FLAGS_HANDLERS_INSTALLED, &boot_ec->flags)) 1405 return 0; 1406 if (!ec_install_handlers(boot_ec)) { 1407 first_ec = boot_ec; 1408 return 0; 1409 } 1410 return -EFAULT; 1411 } 1412 1413 static const struct acpi_device_id ec_device_ids[] = { 1414 {"PNP0C09", 0}, 1415 {"", 0}, 1416 }; 1417 1418 /* Some BIOS do not survive early DSDT scan, skip it */ 1419 static int ec_skip_dsdt_scan(const struct dmi_system_id *id) 1420 { 1421 EC_FLAGS_SKIP_DSDT_SCAN = 1; 1422 return 0; 1423 } 1424 1425 /* ASUStek often supplies us with broken ECDT, validate it */ 1426 static int ec_validate_ecdt(const struct dmi_system_id *id) 1427 { 1428 EC_FLAGS_VALIDATE_ECDT = 1; 1429 return 0; 1430 } 1431 1432 #if 0 1433 /* 1434 * Some EC firmware variations refuses to respond QR_EC when SCI_EVT is not 1435 * set, for which case, we complete the QR_EC without issuing it to the 1436 * firmware. 1437 * https://bugzilla.kernel.org/show_bug.cgi?id=82611 1438 * https://bugzilla.kernel.org/show_bug.cgi?id=97381 1439 */ 1440 static int ec_flag_query_handshake(const struct dmi_system_id *id) 1441 { 1442 pr_debug("Detected the EC firmware requiring QR_EC issued when SCI_EVT set\n"); 1443 EC_FLAGS_QUERY_HANDSHAKE = 1; 1444 return 0; 1445 } 1446 #endif 1447 1448 /* 1449 * On some hardware it is necessary to clear events accumulated by the EC during 1450 * sleep. These ECs stop reporting GPEs until they are manually polled, if too 1451 * many events are accumulated. (e.g. Samsung Series 5/9 notebooks) 1452 * 1453 * https://bugzilla.kernel.org/show_bug.cgi?id=44161 1454 * 1455 * Ideally, the EC should also be instructed NOT to accumulate events during 1456 * sleep (which Windows seems to do somehow), but the interface to control this 1457 * behaviour is not known at this time. 1458 * 1459 * Models known to be affected are Samsung 530Uxx/535Uxx/540Uxx/550Pxx/900Xxx, 1460 * however it is very likely that other Samsung models are affected. 1461 * 1462 * On systems which don't accumulate _Q events during sleep, this extra check 1463 * should be harmless. 1464 */ 1465 static int ec_clear_on_resume(const struct dmi_system_id *id) 1466 { 1467 pr_debug("Detected system needing EC poll on resume.\n"); 1468 EC_FLAGS_CLEAR_ON_RESUME = 1; 1469 ec_event_clearing = ACPI_EC_EVT_TIMING_STATUS; 1470 return 0; 1471 } 1472 1473 static struct dmi_system_id ec_dmi_table[] __initdata = { 1474 { 1475 ec_skip_dsdt_scan, "Compal JFL92", { 1476 DMI_MATCH(DMI_BIOS_VENDOR, "COMPAL"), 1477 DMI_MATCH(DMI_BOARD_NAME, "JFL92") }, NULL}, 1478 { 1479 ec_validate_ecdt, "MSI MS-171F", { 1480 DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star"), 1481 DMI_MATCH(DMI_PRODUCT_NAME, "MS-171F"),}, NULL}, 1482 { 1483 ec_validate_ecdt, "ASUS hardware", { 1484 DMI_MATCH(DMI_BIOS_VENDOR, "ASUS") }, NULL}, 1485 { 1486 ec_validate_ecdt, "ASUS hardware", { 1487 DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer Inc.") }, NULL}, 1488 { 1489 ec_skip_dsdt_scan, "HP Folio 13", { 1490 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"), 1491 DMI_MATCH(DMI_PRODUCT_NAME, "HP Folio 13"),}, NULL}, 1492 { 1493 ec_validate_ecdt, "ASUS hardware", { 1494 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTek Computer Inc."), 1495 DMI_MATCH(DMI_PRODUCT_NAME, "L4R"),}, NULL}, 1496 { 1497 ec_clear_on_resume, "Samsung hardware", { 1498 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD.")}, NULL}, 1499 {}, 1500 }; 1501 1502 int __init acpi_ec_ecdt_probe(void) 1503 { 1504 acpi_status status; 1505 struct acpi_ec *saved_ec = NULL; 1506 struct acpi_table_ecdt *ecdt_ptr; 1507 1508 boot_ec = make_acpi_ec(); 1509 if (!boot_ec) 1510 return -ENOMEM; 1511 /* 1512 * Generate a boot ec context 1513 */ 1514 dmi_check_system(ec_dmi_table); 1515 status = acpi_get_table(ACPI_SIG_ECDT, 1, 1516 (struct acpi_table_header **)&ecdt_ptr); 1517 if (ACPI_SUCCESS(status)) { 1518 pr_info("EC description table is found, configuring boot EC\n"); 1519 boot_ec->command_addr = ecdt_ptr->control.address; 1520 boot_ec->data_addr = ecdt_ptr->data.address; 1521 boot_ec->gpe = ecdt_ptr->gpe; 1522 boot_ec->handle = ACPI_ROOT_OBJECT; 1523 acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id, 1524 &boot_ec->handle); 1525 /* Don't trust ECDT, which comes from ASUSTek */ 1526 if (!EC_FLAGS_VALIDATE_ECDT) 1527 goto install; 1528 saved_ec = kmemdup(boot_ec, sizeof(struct acpi_ec), GFP_KERNEL); 1529 if (!saved_ec) 1530 return -ENOMEM; 1531 /* fall through */ 1532 } 1533 1534 if (EC_FLAGS_SKIP_DSDT_SCAN) { 1535 kfree(saved_ec); 1536 return -ENODEV; 1537 } 1538 1539 /* This workaround is needed only on some broken machines, 1540 * which require early EC, but fail to provide ECDT */ 1541 pr_debug("Look up EC in DSDT\n"); 1542 status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device, 1543 boot_ec, NULL); 1544 /* Check that acpi_get_devices actually find something */ 1545 if (ACPI_FAILURE(status) || !boot_ec->handle) 1546 goto error; 1547 if (saved_ec) { 1548 /* try to find good ECDT from ASUSTek */ 1549 if (saved_ec->command_addr != boot_ec->command_addr || 1550 saved_ec->data_addr != boot_ec->data_addr || 1551 saved_ec->gpe != boot_ec->gpe || 1552 saved_ec->handle != boot_ec->handle) 1553 pr_info("ASUSTek keeps feeding us with broken " 1554 "ECDT tables, which are very hard to workaround. " 1555 "Trying to use DSDT EC info instead. Please send " 1556 "output of acpidump to linux-acpi@vger.kernel.org\n"); 1557 kfree(saved_ec); 1558 saved_ec = NULL; 1559 } else { 1560 /* We really need to limit this workaround, the only ASUS, 1561 * which needs it, has fake EC._INI method, so use it as flag. 1562 * Keep boot_ec struct as it will be needed soon. 1563 */ 1564 if (!dmi_name_in_vendors("ASUS") || 1565 !acpi_has_method(boot_ec->handle, "_INI")) 1566 return -ENODEV; 1567 } 1568 install: 1569 if (!ec_install_handlers(boot_ec)) { 1570 first_ec = boot_ec; 1571 return 0; 1572 } 1573 error: 1574 kfree(boot_ec); 1575 kfree(saved_ec); 1576 boot_ec = NULL; 1577 return -ENODEV; 1578 } 1579 1580 static int param_set_event_clearing(const char *val, struct kernel_param *kp) 1581 { 1582 int result = 0; 1583 1584 if (!strncmp(val, "status", sizeof("status") - 1)) { 1585 ec_event_clearing = ACPI_EC_EVT_TIMING_STATUS; 1586 pr_info("Assuming SCI_EVT clearing on EC_SC accesses\n"); 1587 } else if (!strncmp(val, "query", sizeof("query") - 1)) { 1588 ec_event_clearing = ACPI_EC_EVT_TIMING_QUERY; 1589 pr_info("Assuming SCI_EVT clearing on QR_EC writes\n"); 1590 } else if (!strncmp(val, "event", sizeof("event") - 1)) { 1591 ec_event_clearing = ACPI_EC_EVT_TIMING_EVENT; 1592 pr_info("Assuming SCI_EVT clearing on event reads\n"); 1593 } else 1594 result = -EINVAL; 1595 return result; 1596 } 1597 1598 static int param_get_event_clearing(char *buffer, struct kernel_param *kp) 1599 { 1600 switch (ec_event_clearing) { 1601 case ACPI_EC_EVT_TIMING_STATUS: 1602 return sprintf(buffer, "status"); 1603 case ACPI_EC_EVT_TIMING_QUERY: 1604 return sprintf(buffer, "query"); 1605 case ACPI_EC_EVT_TIMING_EVENT: 1606 return sprintf(buffer, "event"); 1607 default: 1608 return sprintf(buffer, "invalid"); 1609 } 1610 return 0; 1611 } 1612 1613 module_param_call(ec_event_clearing, param_set_event_clearing, param_get_event_clearing, 1614 NULL, 0644); 1615 MODULE_PARM_DESC(ec_event_clearing, "Assumed SCI_EVT clearing timing"); 1616 1617 static struct acpi_driver acpi_ec_driver = { 1618 .name = "ec", 1619 .class = ACPI_EC_CLASS, 1620 .ids = ec_device_ids, 1621 .ops = { 1622 .add = acpi_ec_add, 1623 .remove = acpi_ec_remove, 1624 }, 1625 }; 1626 1627 int __init acpi_ec_init(void) 1628 { 1629 int result = 0; 1630 1631 /* Now register the driver for the EC */ 1632 result = acpi_bus_register_driver(&acpi_ec_driver); 1633 if (result < 0) 1634 return -ENODEV; 1635 1636 return result; 1637 } 1638 1639 /* EC driver currently not unloadable */ 1640 #if 0 1641 static void __exit acpi_ec_exit(void) 1642 { 1643 1644 acpi_bus_unregister_driver(&acpi_ec_driver); 1645 } 1646 #endif /* 0 */ 1647